20028657601 has 4 divisors (see below), whose sum is σ = 20058958804. Its totient is φ = 19998356400.

The previous prime is 20028657581. The next prime is 20028657611. The reversal of 20028657601 is 10675682002.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6025485376 + 14003172225 = 77624^2 + 118335^2 .

It is a cyclic number.

It is not a de Polignac number, because 20028657601 - 2¹³ = 20028649409 is a prime.

It is a super-2 number, since 2×20028657601² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20028657611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15149610 + ... + 15150931.

It is an arithmetic number, because the mean of its divisors is an integer number (5014739701).

Almost surely, 2^20028657601 is an apocalyptic number.

It is an amenable number.

20028657601 is a deficient number, since it is larger than the sum of its proper divisors (30301203).

20028657601 is an equidigital number, since it uses as much as digits as its factorization.

20028657601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30301202.

The product of its (nonzero) digits is 40320, while the sum is 37.

The spelling of 20028657601 in words is "twenty billion, twenty-eight million, six hundred fifty-seven thousand, six hundred one".